A&P Ch 13 and 14
The spinal cord continues to elongate until about age
4 years
Which of the following is a function of the hypothalamus?
All of the answers are correct
Which of the following help to protect the brain?
All of the answers are correct.
Which of the following is a property of the blood-brain barrier?
All of the answers are correct.
Which of the following is true regarding an epidural block?
All of the answers are correct.
The spinal cord is part of the ________ nervous system.
Central
In the spinal cord, white matter is separated into ascending and descending tracts organized as
Columns
Describe the nomenclature of the spinal nerves
Each spinal nerve inferior to the first thoracic vertebra takes its name from the vertebra immediately superior to it. Thus, spinal nerve T1 emerges immediately inferior to vertebra T1, spinal nerve T2 emerges below vertebra T2, and so forth. The arrangement differs in the cervical region, because the first pair of spinal nerves, C1, passes between the skull and the first cervical vertebra. For this reason, each cervical nerve takes its name from the vertebra immediately inferior to it. So, nerve C2precedes vertebra C2, and so on. The transition in numbering occurs between the last cervical vertebra and first thoracic vertebra. The spinal nerve at this location is designated C8. Therefore, while there are seven cervical vertebra, there are eight cervical nerves
Divisions of the cerebral hemispheres that are named after the overlying skull bones are
Lobes
Tina falls while climbing a tree and lands on her back. Her frightened parents take her to the emergency room, where she is examined. Her knee-jerk reflex is normal and she exhibits a plantar reflex (negative Babinski reflex). These results suggest that Tina has
NO back injury
Describe the gross anatomy of the spinal cord
The series of vertebrae forming the axis of the skeleton and protecting the spinal cord; divided into five groups by location: cervical, thoracic, lumbar, sacral and coccygeal groups. aka. spinal column, spine.
In which of the following would the delay between stimulus and response be greater?
a polysynaptic reflex
Figure 13-1 The Spinal Cord Use Figure 13-1 to answer the following question: Identify the structure labeled "10."
anterior gray commissure
At the optic chiasm,
axons from the medial halves of each retina cross.
The ventral rami of spinal nerves C5 to T1 contribute fibers to the ________ plexus.
brachial
The ________ reflex complements the flexor reflex by activating contralateral muscles.
crossed extensor
The term used to describe the crossing over of a tract to the side of the nervous system opposite to where the axons originated is
decussation
Specialized ________ cells form the secretory component of the choroid plexus.
ependymal
The postganglionic fibers that connect an autonomic ganglion in the thoracic or lumbar region with the spinal nerve and contain postganglionic fibers that innervate glands in the body wall or smooth muscles in limbs are
gray rami communicantes
Emotions and behavioral drives are associated with the
hypothalamus
The ________ provides the principal link between the nervous and endocrine systems.
hypothalamus
Reflexes that activate muscles on the same side of the body as the stimulus are called
ipsilateral
Autonomic centers that control blood pressure, heart rate, and digestion are located in the
medulla oblongata.
The structure of the brain that carries ascending sensory information to the thalamus is the
midbrain
The gray horns of the spinal cord contain mainly
neuron cell bodies
The layer of connective tissue that surrounds a fascicle within a peripheral nerve is the
perineurium
The layer of the meninges in direct contact with the spinal cord is the
pia mater
A complex, interwoven network of nerves is called a
plexus
Figure 13-1 The Spinal Cord Use Figure 13-1 to answer the following question: Identify the structure labeled "4."
posterior gray horn
Which of these is not one of the main divisions of the adult brain?
prosencephalon
Which of the following is not a function of cerebrospinal fluid?
provides ATP for impulse transmission
If the dorsal root of a spinal nerve is severed,
sensory input would be blocked.
The posterior horns of the spinal cord contain mainly
sensory nuclei
What contains a spider web-like network of cells and fibers through which cerebrospinal fluid flows?
subarachnoid space
Cerebrospinal fluid flows within the
subarachnoid space.
The corpora quadrigemina is composed of the
superior and inferior colliculi
Figure 14-1 The Circulation of Cerebrospinal Fluid Use Figure 14-1 to answer the following question: Identify the structure labeled "9."
superior sagittal sinus
Postganglionic fibers of the autonomic nervous system that innervate internal organs are
sympathetic nerves
The preganglionic fibers that connect a spinal nerve with an autonomic ganglion in the thoracic and lumbar region of the spinal cord and carries visceral motor fibers that are myelinated form the
white rami communicantes.
What is the function of the spinal meninges?
• The spinal meninges are a series of specialized membranes that provide physical stability and shock absorption for the spinal cord • The spinal meninges consist of three layers - Dura mater - Arachnoid - Pia mater
Figure 14-1 The Circulation of Cerebrospinal Fluid Use Figure 14-1 to answer the following question: Identify the structure labeled "8."
arachnoid granulation
Cerebrospinal fluid enters the blood circulation at the
arachnoid granulations
The white matter of the cerebellum forms a branching array called the
arbor vitae.
The medulla oblongata regulates
blood pressure and respiration.
Reflexes that activate muscles on the opposite side of the body as the stimulus are called
contralateral
The pineal gland is part of the
diencephalon
The folds of the surface of the cerebrum
increase the surface area of the cerebrum.
The reflex movement of the head toward a loud noise is directed by the mesencephalon. Which nuclei accomplish this?
inferior colliculi
The ________, a narrow stalk, connects the hypothalamus to the pituitary gland.
infundibulum
Reflexes based on synapses formed during development are ________ reflexes.
innate
The white matter of the spinal cord is mainly
myelinated axons.
The layer of the meninges that closely follows every gyrus and sulcus is the
pia mater
What structure is covered by many blood vessels and adheres tightly to the surface of the brain?
pia mater
The white ramus and the gray ramus collectively are called the
rami communicantes
Spinal interneurons inhibit antagonist motor neurons in a process called
reciprocal inhibition
The anterior horns of the spinal cord contain mainly
somatic motor nuclei
Figure 13-1 The Spinal Cord Use Figure 13-1 to answer the following question: What is the function of the structure labeled "12"?
somatic sensory receiving
A dorsal and ventral root of each spinal segment unite to form a
spinal nerve
The reflex that prevents a muscle from exerting too much tension is the ________ reflex.
tendon
Sensory information is processed and relayed to the cerebrum by the
thalamus
List the four major nerve plexuses formed by the ventral rami of the spinal nerves
the cervical plexus, the brachial plexus, the lumbar plexus, and the sacral plexus
The subdural space lies between
the dura mater and the arachnoid mater.
Describe the use of reflexes in diagnostic testing
the evaluation of somatic reflexescan provide valuable information about the location of damage to the spinal cord or spinal nerves
Describe the peripheral ramification (branching) of spinal nerves
the spinal nerve forms just lateral to the intervertebral foramen, where the dorsal and ventral roots unite; the first branch from the spinal nerve carries visceral motor fibers to a sympathetic ganglion; the dorsal ramus of each spinal nerve contains somatic motor and visceral motor fibers that innervate the skin and muscles of the back
Chambers within the brain that contain cerebrospinal fluid are called
ventricles
Describe: Stretch reflexes The tendon reflex Withdrawal reflexes The flexor reflex Crossed extensor reflexes
- increasing muscle length activates a sensory neuron, which triggers contraction of the muscle to counteract the stimulus - monitors the external tension produced during a muscle contraction and prevent tearing and breaking of the tendon - a family of reflexes that move the affected parts of thebody away from a source of stimulation - pulls the affected part away from the stimulus - a contralateral reflex because the motor respinse occurs on the opposite side from the stimulus
Describe the: Cervical Plexus Brachial Plexus Lumbar Plexus Sacral Plexus
- it arises from the fusion of the ventral rami of spinal nerves C1-C5; it innervates the muscles of the neck and controls the diaphragmatic muscles - the brachial plexus arises from the fusion of the ventral rami of spinal nerves C5-T1; it innervates the pectoral girdle and upper limbs - arise from the fusion of the ventral rami of the lumbar segments of the spinal cord, T12-L4 - arise from the fusion of the ventral rami of sacral segments of the spinal cord, L4-S4
Describe the: Dura Mater Arachnoid Pia Mater
-The dura mater forms the outermost covering of the spinal cord. - In most anatomical and histological preparations the subdural space separates the dura mater and pia mater - The pia mater is the innermost meningeal layer and consists of a network of elastic and collagen fibers firmly bound to the underlying neural tissue
The ventral root of a spinal nerve contains
axons of motor neurons.
If the pons was damaged, which of the following functions would be affected?
breathing
How are reflexes classified?
by their development (innate or acquired), the nature of the resulting motor response (spinal or cranial), the complexity of the neural circuit involved (somatic or visceral), or the site of information processing (monosynaptic or polysynaptic)
All of the following are true of neural reflexes except that they
cannot be modified by the brain.
The dorsal root ganglia mainly contain
cell bodies of sensory neurons
Overseeing the postural muscles of the body and making rapid adjustments to maintain balance and equilibrium are functions of the
cerebellum
Figure 14-1 The Circulation of Cerebrospinal Fluid Use Figure 14-1 to answer the following question: What is produced by the structure labeled "2"?
cerebrospinal fluid
A neural cortex is found on the surface of the
cerebrum
What are the six major regions of the brain?
cerebrum, diencephalon, mesencephalon, pons, cerebellum, and medulla oblongata
Figure 14-1 The Circulation of Cerebrospinal Fluid Use Figure 14-1 to answer the following question: Identify the structure labeled "1."
choroid plexus
The ________ connects the two sides of the cerebrum.
commissural fibers
Figure 13-1 The Spinal Cord Use Figure 13-1 to answer the following question: What is the function of the structure labeled "14"?
control of visceral effectors
The specific strip of skin that is innervated by a specific spinal nerve is called a
dermatome
List the five patterns of interaction among neurons
divergence, convergence, serial processing parallel processing, reverberation
The tough, fibrous, outermost covering of the spinal cord is the
dura mater.
The layer of connective tissue that surrounds individual axons within a peripheral nerve is termed the
endoneurium
The outermost connective-tissue covering of nerves is the
epineurium
The dural fold that projects into the longitudinal fissure between cerebral hemispheres is called the
falx cerebri
The ________ is a strand of fibrous tissue that provides longitudinal support to the spinal cord as a component of the coccygeal ligament.
filum terminale
Which of the following is not a property of the limbic system?
functions in maintaining homeostasis in cold weather
Axons crossing from one side of the spinal cord to the other within the gray matter are found in the
gray commissures
The folds of the cerebrum are called
gyri
The brain requires a substantial blood supply. The vessels that deliver blood to the brain are the
internal carotid and vertebral arteries
The most complicated spinal reflexes are called
intersegmental reflex arcs.
What five characteristics are shared by all polysynaptic reflexes
involvement of pools of interneurons intersegmental distribution involvement of reciprocal innervation motor response prolonged by reverberating circuits cooperation of reflexes to produce a coordinated, controlled response
The hypothalamus is a key player in the endocrine system because
it controls the pituitary gland directly underneath it.
Bill contracts a viral disease that destroys cells in the posterior gray horns in his spinal cord. As a result, which of the following would you expect?
loss of sensation in his torso
In a(n) ________ reflex, a sensory neuron synapses directly on a motor neuron.
monosynaptic
As you ascend from the medulla oblongata to the cerebrum, the functions of each successive level become
more complex.
Recognized neuronal circuit patterns include all of the following except
multipolar
The spinal cord consists of four regions and ________ segments.
thirty-one